


For The Sake Of Tradition

by angelcult



Series: .COM [1]
Category: Ao no Exorcist | Blue Exorcist
Genre: Boot Worship, Chastity Device, Dom/sub Undertones, Filming, Foursome - M/M/M/M, M/M, Mating Cycles/In Heat, Scent Kink, Semi-Public Sex
Language: English
Status: Completed
Published: 2020-04-07
Updated: 2020-04-07
Packaged: 2021-03-02 00:08:18
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,140
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23535802
Author URL: https://archiveofourown.org/users/angelcult/pseuds/angelcult
Summary: Rin, having never heard of and therefore never having gone through with it, finally learns of the strange heat tradition seen within the halls of royal demons with the help of his brothers.
Relationships: Amaimon/Mephisto Pheles, Okumura Rin/Okumura Yukio
Series: .COM [1]
Series URL: https://archiveofourown.org/series/1853956
Comments: 2
Kudos: 125





	For The Sake Of Tradition

“What do you mean there’s a  _ heat tradition?” _

“I mean it as I said it, Rin, a heat tradition typical among full-blooded Royal demons. I’m actually surprised that you have heats, given your half-breed nature.” Mephisto commented lightly from where he sat on the edge of Yukio’s bed. 

Amaimon was beside him, though he didn’t seem to be very tuned in with what was happening around him, daydreaming about something or another as he stared off, one hand curled around Mephisto’s wrist. 

“I mean, you’ve gone through a few of them before, haven’t you?” Mephisto asked, giving a pointed glance to the barely hidden bite on his neck.

Rin’s hand flew up to cover it, but the motion didn’t hold much power as his face was now flushing red.

“I bet that genius brother of yours has been helping, hasn’t he?” Amaimon commented, smiling a little at Rin, blue eyes shining in a way that was not unlike his own. 

“Yeah, well, he would have known about a tradition or whatever, right?”

Mephisto sat up a little straighter and smiled cattily.

“Not particularly. You see, most demons don’t have heats,” As he explained, he climbed to his feet, Amaimon’s hand slipping away from his wrist as he walked over to Rin. “But you’re a little different, being the son of Satan, and all that.”

As he spoke, he stepped behind his younger brother, sliding a hand down his chest to his stomach, and then a little lower. 

“I suppose that if you were a biological woman, you’d have a womb here.” He tapped his nails lightly as he slid his hand beneath Rin’s shirt. The younger boy leaned back against the other, seemingly unaware of his own actions. 

“But seeing as you don’t, you can’t get pregnant and I suppose I could thank my grandfather for that.”

“Okay, okay, but that isn’t explaining much of anything.” Rin batted at the hand beneath his clothes but made no actual moves to stop him from running his nails up and down his flat stomach, once again melting back against Mephisto’s chest.

“You’re just talking in circles again.” 

“What I’m saying is, little brother, that even if you can’t have children, we still have to follow the tradition until you physically can’t go anymore.” 

Rin rolled his eyes, spinning in Mephisto’s loose grip so that he could look up at the other.

“And what  _ is  _ the tradition, exactly?”

Mephisto chuckled under his breath, fingers lightly gripping Rin’s cheeks and smushing them a little before speaking, as if he was merely commenting on the weather.

“You’re fucked by members of your immediate family until it takes, to put it crudely and simply.”

Rin swallowed and looked away from Mephisto, only to catch eyes with himself in the full-length mirror leaning against the wall. 

He wasn’t particularly against it and well, it was  _ tradition _ and all that…

Rin grunted when additional weight leaned against his back and he felt Amaimon nudging his nose against his neck. He tilted his head to the side and the older demon immediately mouthed and licked at the mark there.

“It won’t be long now, will it, Rin? You’re starting to smell sweeter already.”

A hand, too large to be Amaimon’s, slid down Rin’s chest to the inside of his thigh. 

Amaimon looked over Rin’s shoulder and smiled at the heavy look in his brother’s eyes. 

“But I suppose we can have some fun before the real show begins.”

  
  


—

Rin wasn’t nearly foolish enough to think that Yukio hadn’t already been told everything, but it was still a bit surprising to see him going along with what Mephisto was explaining to him. 

“How do we know he isn’t just fucking with us?” Rin asked with a slight raise of his eyebrow and Yukio rolled his eyes before tapping Rin’s cheek with two fingers.

“Don’t worry, I researched everything,” Rin sighed in relief but Yukio kept talking. “But something tells me that you wouldn’t have cared either way.”

“We’re in the middle of a field, if anyone even glances this way..” Rin nodded towards the football field a little ways from them. 

If anything, the field was mostly for show, as no one was attempting to tackle the demons they were exorcising (at least Rin  _ hoped  _ they weren’t) but it tended to be a general hang out spot for between classes and lunch. Traffic in that area had slowed with the beginning of exam season and the gradual shift in temperature but that didn’t mean it was  _ completely  _ unused.

Rin shuddered at the thought of it, anyone could see, even with the great distance between them, especially if they were curious enough to get closer.. 

“Cold?” Yukio asked in jest, swiping his thumb back and forth over Rin’s cheek. He was warm and pink with heat, softly leaning into his brother’s touch with an ease of familiarity. 

“Yukio? Is he ready?” 

Rin rolled his eyes, leaning against Yukio’s chest tilting his head to peek at Mephisto with one eye, lips tilted down in a curious frown. He scanned the man before his eyes fell onto what was being held in his hands.

“What’s that?” 

He pulled away from Yukio a little only to be pulled back by his tie.

“It’s a bitchsuit, little brother. And given the predicament you’ll soon find yourself in, it’s rather fitting.” 

Rin jolted a little at the sound of Amaimon’s voice, it was so close. Just over his shoulder, the stick of a lollipop hit his cheek and Rin turned his head so that he was eye to eye with the other, a mischievous glint in his half-brother’s blue eyes.

He pulled the lollipop out and pushed it against Rin’s lips. He accepted it and Amaimon smiled before motioning to Mephisto again. 

“Rin.”

Yukio’s voice was steady, and Rin’s attention immediately snapped to his younger brother. Yukio took the candy and tossed it aside before ruffling Rin’s hair.

“Heel.” 

Rin slid to his knees without hesitation, glad that he wasn’t wearing his school uniform as he found himself kneeling in the grass.

“Good boy.” Yukio praised softly and Rin pushed back up into the hand in his hair. After running his hand through, Yukio lowered himself down to Rin’s height, tilting his head back a little so that their eyes met.

“You’ve never been in a bitchsuit, I’m assuming, have you?” Yukio asked and Rin shook his head,  _ no.  _

Yukio hummed softly before continuing on to explain what it was and how it was worn. 

“Your hands will be restrained, is that a problem?”

Yukio watched as Rin’s eyes darted away from him, visibly in thought. His hands flexed at his sides, eyebrows drawing up before he nodded, visibly unsure but willing to try at least once.

“Good boy, Rin, very good demon.” He pressed a kiss to his forehead before standing and looking at Mephisto. He tilted his head to Rin and stepped aside.

He backed right into Amaimon’s arms, who seemed more content with pressing kisses to the skin of his neck that wasn’t hidden by the high collar of his overcoat. 

Mephisto waved a finger at Rin and his clothes disappeared. He watched in mild amusement as Rin’s tail wrapped around his own arm before he looked up to Mephisto and then down to the piece of clothing in his hands. 

“Are you going to put it on me?”

“Rin, I don’t believe you were told to speak.” Yukio spoke up after pulling Amaimon away from his mouth with a hand firmly twisted in his hair. 

He jolted and hunched in on himself, but if the shudder that ran through him was anything to go by, he didn’t particularly mind the reprimand. 

“Up, boy, let’s get this on. I suppose a little magic would have it on you in a jiff, but I’d much prefer watching you fit into it.” Mephisto teased, pulling his brother up to his feet. 

Rin stumbled a little, and Mephisto found himself pulling the younger demon closer. His heat scent was  _ sweet,  _ which Mephisto hadn’t quite expected given that Rin didn’t seem to eat as many sweets as Amaimon and himself (though perhaps it was because his body was aware of the demons he was surrounded with, who craved sweet things almost as much as mischief). 

He nosed up Rin’s neck, biting into the already fading mark there, drawing out a loud whimper that trailed into a small moan when he bit down a little harder.

Mephisto’s eyebrows raised and he pulled back, staring at his already glassy-eyed brother.

“You’re a pain slut too? Good to know.”

Rin was particularly pliant, allowing himself to be dressed with ease.

When Mephisto went to pull the cover over Rin’s hands, he yanked away, his first real show of complaint since they began and the older demon stopped, gently running his fingers up and down his side, he knew he’d be able to feel it through the fairly thin rubber. 

“What’s the matter?”

“My hands..” He didn’t explain further and Mephisto nodded in understanding, pressing a kiss to his brother’s mouth. 

“How about this, a little compromise. I’ll strap you in  _ but,  _ if you don’t like it, you can melt through the rubber with those pretty blue flames. Deal?”

Mephisto tilted his head and he got a slight nod in response. He ruffled Rin’s hair and then continued on. 

Once he was finished, minus the belt-like strappings, Mephisto tugged a whining brother towards himself to lace the collar around his neck. After it was tightened, he slipped two fingers beneath to see if there was enough give. 

“Oh, I should perhaps mention this isn’t part of the tradition, the suit,” Mephisto began, tugging Rin closer to softly speak to him. “That’s just for  _ me. _ ”

The moan he got in response was more than worth it. 

“Down, all fours, let me add the finishing touches.” 

Rin did as he was told, pausing when Yukio kneeled in front of him. His shirt was unbuttoned and his chest riddled with bites and hickeys, he could see Amaimon’s pleased expression from where he was kneeling.

“Leave his arms unbuckled. Don’t want him messing up that pretty face if he melts through it and falls.”

Mephisto nodded and finished up the process, standing going beside his brothers to look Rin over. 

The sleek black suit was mostly encompassing him, save for his ass and the small of his back (as Mephisto wasn’t too keen on finding out the flexibility of Rin’s tail), the half-done straps put him at a rather appealing angle that accentuated and elongated the natural curve of his back.

The smell of heat was stronger now, enough that Yukio seemed to even be affected, if the sharpening of his canines and the slit in his pupils was anything to go by. 

Rin’s loud whimper jolted them out of their staring, his tail thrashing back and forth in impatience. 

“ _ Yuki.”  _

His drawn out moan had the younger twin’s eyes snapping to him before they darted back down to his tail. 

“Go on, you  _ are  _ his twin after all. We’ll do you the honor of allowing you to breed him first.”

Mephisto watched as Yukio approached his brother, trailing a hand from his shoulder down his back.

“Brother,” Amaimon began and Mephisto glanced at him, nodding for him to continue. “Don’t you think it’d be better if we had something to.. Remember this by? It is our  _ first  _ heat with him after all..”

Mephisto’s smirk widened and he nodded, snapping his fingers at the same time Rin gasped, rocking his hips back onto Yukio’s fingers, they were curled inside of him and even at the angle they stood, Amaimon and Mephisto could tell that he was thrusting and rubbing against his prostate. 

He was attempting to muffle his moans into his arm, where he was biting down hard enough that Mephisto briefly worried he’d bite through the rubber.

“Ah, ah, bad boy, Rin. Let us hear you, let the camera hear you too.”

Both twins jolted at that and immediately looked up at the camera floating before them. It was angled down towards Rin’s face, and Mephisto hoped it picked up the way his blush darkened and his eyes rolled back as he moaned again, clearly a fan of being filmed.

Mephisto and Amaimon were delighted in the loud moans that followed when Yukio harshly pushed in.

“Fuck, fuck, I’m gonna c-  _ what the fuck-!” _

Mephisto was more than pleased with the dazed glare that was thrown his way as he stepped in front of Rin, his boots stopping a few inches from his mouth.

“We’ve barely started and you’re already about to finish? Why, Rin,” He was toeing his boots off, smirking mischievously.

“Lunch hasn’t even let out yet, and- don’t you look at me like that, your little glare is ruined with that fucked out look on your face.” He dropped into a crouch, grabbing Rin by his hair and pushing them against the opening of his boots.

He tried to yank away, but it seemed more like an attempt to have hair pulled then to actually pull away from Mephisto’s ministrations.

Yukio swore under his breath, pushing harder into his brother, eyes falling shut as his glasses that were pushed up into his bangs slipped down his face. 

His hips stuttered forwards, pulling Rin flush against himself as he came, leaning over his back.

Rin groaned, dropping his nose into the older demon’s boot, no doubt a pathetic attempt to pout and hide his face. Mephisto smiled when he leaned a bit to the side and spared a glance between his open legs, his cock forced into a six ring, silver chastity cage. 

Realistically, it should have been on him much,  _ much  _ earlier (especially not right when his brother was on the brink of orgasm) but it was nothing some unconventional magic couldn’t fix. 

Yukio pulled out, staring down at where his cock had just been. He placed his hands on either side of Rin’s ass that was red from where his hips had repeatedly met it in a punishing pace. 

He spread him open, eyes following the cum and slick that leaked out of him and down the backs of his thighs.

Amaimon pushed himself against Yukio’s side, pants now gone. 

“You’ve gotta share him, Yukio.” He chirped, pecking him once on the lips before nudging him out of the way with his hip, pushing into Rin with little finesse or hesitance.

His brother moaned, pushing his hips back into the thrusts the followed, Amaimon’s nails digging into his hips. 

His eyes fell closed and he moaned softly, hunching over Rin’s back some. He was  _ so so  _ hot around him, a bit hotter than his temperature should have been if he wasn’t affected by the heat, the wet sounds of Yukio’s cum and Rin’s own slick echoing loudly through the open area, paired with the slapping of sweat-slick skin had Rin wondering if anyone would hear them.

_ If anyone saw me like this, I’d be ruined,  _ Rin’s train of thought was cut short when Yukio lifted his head up with the toe of his boot. 

“If you can still think, we must not be doing this properly.” 

There was a flash of light and a click of the camera, it made Rin’s eyes fall closed again, pushing his hips back. His tail wrapped around Amaimon’s wrist in a futile attempt to keep his close.

“Please Yuki, I just want to cum, it’s so hot, it’s  _ so fucking hot _ -“ He cut himself off with a moan, curling in on himself and rutting his hips forward into empty air in a futile attempt to get friction.

Mephisto ran his hand through Rin’s hair as he shuddered through the vestiges of what the elder demon assumed was a dry orgasm. 

“Aren’t you just a pitiful little sight to see, Rin,” Mephisto cooed, pathetic little whines were his only response as he kicked his own boots away and motioned to Yukio. 

“Go on, you aren’t done yet.” 

Rin went to reply when Amaimon let out a choked gasp and his nails dug harder into his hips, drawing pinpricks of blood to the surface as he came. 

Yukio’s scent was strong when Rin’s nose was shoved into his boot and he scrambled back against the hand in his hair, though he clearly wasn’t trying to intentionally free himself as the grip did not loosen and he was shoved down harder. 

“Just one more, big brother, and then we’ll let you finish.”

In the distance, there was a chime and Rin’s eyes widened when he was let go, and he went to look over his shoulder towards the football field when he was yanked back forward with his collar.

“Scared someone will see? It would be a shame if your classmates got an eyeful of how much of a slut you are, letting your brothers breed you out in the open where anyone could see,” Rin moaned softly at Yukio’s words, tail now thrashing around freely as Amaimon was no longer behind him.

The feeling of Mephisto pushing in was more noticeable than Yukio and Amaimon, not that they weren’t decently sized themselves, he was just notably  _ bigger _ .

“Look up, look at me,” Rin did as he was asked, panting softly. His gaze was unfocused and his skin was a ruddy pink.

The camera floated a little closer to get the minute details. 

“Mephisto is really big, isn’t it? He’s filling you up more than Amaimon and I could but that’s alright, you don’t mind it, do you?” His voice cooed a little as he watched as Rin’s eyes tightly closed when Mephisto started to fuck into him, the pace was harsh and deep, forcing out moans and small  _ “ah, ah, ah”’ _ s with every thrust. 

Yukio met Mephisto’s eyes over his brother as Amaimon leaned into his shoulder, trailing more kisses and bites up his neck. 

Rin let out a particularly loud moan that drew three pairs of eyes back to him as he shook and moaned his way through another dry orgasm, Mephisto not pausing throughout it, having only slowed a little before his pace quickened to its previous one. 

Amaimon and Yukio watched, enthralled and a little turned on despite having already come previously as Mephisto fucked Rin to tears, his eyes wet but notably pleased when he was came in for the third and final time that evening.

Mephisto pulled out and Rin slumped forward, panting and softly whimpering. 

Amaimon leaned forward, with the intent of removing the cage when Yukio placed a hand on his chest and smiled down at his brother.

“Leave it.” Rin met his eyes as he spoke and Yukio smiled sweetly.

“He’ll last so much longer this way.”

  
  
  



End file.
